Frigatebirds

Frigatebirds are large seabirds usually found over tropical oceans. They are large, black or black–and–white, with long wings and deeply-forked tails. The males have inflatable coloured throat pouches. They do not swim or walk, and cannot take off from a flat surface. Having the largest wingspan to body weight ratio of any bird, they are essentially aerial, able to stay aloft for more than a week.